If insight can change the brain, then insight must be beyond the brain

Some people say, that there nothing is beyond the brain. The materialists.

But if insight can change the brain, then this is implying, that insight somehow is beyond the brain.

This doesn´t have to be something mystical.

If an alcoholic is having the insight, that he must stop his abuse, and actually is stopping, then this insight is affecting his brain cells. And this insight must therefore be something different than the brain.

Please, go deep into this question.